Diamondbacks injury updates: Zac Gallen, Merrill Kelly to begin throwing programs

PHOENIX — Arizona Diamondbacks injured starting pitchers Zac Gallen and Merrill Kelly will each begin a throwing program on Tuesday, manager Torey Lovullo said amid a slew of injury updates on Monday.

Arizona’s critical 1-2 punch has very different timelines, however. Kelly has been on the injured list since April 20 (right shoulder strain), while Arizona added Gallen (right hamstring strain) to the 15-day IL on Friday.

Of Kelly, Lovullo said, “What he missed on the front side, he’s got to build up on the backside.”

Lovullo explained Kelly is tracking to return around the All-Star break, while the hope with Gallen is his stint won’t be much longer than the 15 days.

“I think that’s what we’re all hoping for. … I’m sure when he’s throwing, he’s not going to feel much of the discomfort he was feeling,” Lovullo said of Gallen.

“We just got to be careful about how it heals and when he starts to really stress that and push off of it. So when does that start? I don’t know. I don’t know what the timeline will be.”

Kelly only made four starts before landing on the IL, while Gallen started 11 games before exiting Thursday against the New York Mets. Gallen missed two weeks with a hamstring strain in 2021.

When will Eduardo Rodriguez debut?

Lovullo said starting pitcher Eduardo Rodriguez (left shoulder strain) has been throwing up to 90 feet.

“I think the progression is 90, 105, 120, flat ground and then get on a mound and throw a bullpen,” Lovullo said. “He’s going to continue to get evaluated. He’s going to continue to get imaging. We’ve got to make sure we hit these landmarks and everything’s showing up the right way before we take next steps.”

Lovullo said not to hold him to a specific timeline but expects to get Rodriguez back around the All-Star break, similar to Kelly.

Rodriguez has yet to make his D-backs debut after signing a four-year, $80 million contract. The southpaw suffered a shoulder strain in spring training.

He began throwing within 10 days of the injury, but a setback halted his progress, a lesson for the D-backs who have slowed him down this time.

“It’s not gonna turn around and be next week. It’s gonna take a little bit of time,” Lovullo said.

The Diamondbacks will have to make a less experienced rotation work behind veteran Jordan Montgomery until Gallen presumably returns first. Brandon Pfaadt, Ryne Nelson, Slade Cecconi and Blake Walston round out the five. Nelson leads that quartet with 38 career starts entering Monday.

Geraldo Perdomo to start rehab assignment

Shortstop Geraldo Perdomo (torn meniscus) is scheduled to play seven innings in the Arizona Complex League Monday and then hop on a plane to join the Triple-A Reno Aces.

Perdomo will not play Tuesday but jump in the lineup Wednesday, Lovullo said. He has already played in two ACL games, but Lovullo did not have a specific number of days in mind before his return to Arizona.

“He’s going to tell us piece by piece as to how he’s feeling by the type of reps he’s getting, the movements he’s making and then we’ll listen to his words pre and post,” Lovullo said. “He’s getting very, very close.”

When will Alek Thomas play in games?

Center fielder Alek Thomas (right hamstring strain) is getting consistent live at-bats, but he has yet to run the bases.

“He’s running forward, but not at full speed,” Lovullo said. “Getting ready to get on the bases I think later this week.”

Lovullo said if everything plays out according to plan, Thomas can start getting into games next week.

Diamondbacks injury notes

– Reliever Luis Frias (right shoulder inflammation) will start pitching for Reno on Tuesday.

– Reliever Miguel Castro (right shoulder inflammation) will throw on flat ground on Tuesday.

– The San Francisco Giants are in Phoenix for three games against the D-backs starting Monday night. San Francisco placed left-handed starter Blake Snell on the 15-day IL (groin) and activated outfielder Michael Conforto. Longtime Diamondbacks shortstop Nick Ahmed (wrist) is on the IL for San Francisco.

First pitch is at 6:40 p.m. on 98.7 and the Arizona Sports app. 

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